A major Midwest US utility power station upgraded its boiler feed water make-up system by replacing the conventional lime softening and sand/gravel bed filtration with an integrated membrane based system. The conventional system was resulting in the use of large quantities of coagulant, lime, acid and caustic to produce demineralized water. The system, besides being expensive to operate, was unable to cope with the sudden changes in the incoming raw water quality from the nearby lake. The integrated membrane (IM) system, consisting of Microfiltration and Reverse Osmosis sub-systems, significantly improved the run time of the deep bed ion-exchange as well as the pre-coat condensate polishing system. As a result of the upgrade, the plant saw reduction of over 90% in the operating cost of the boiler feed water makeup system along with higher reliability and efficiency of the overall power plant. The paper discusses the experience and the lessons learned during the implementation of the IM system.
Hybrid System Coupling Moving Bed Bioreactor with UV/O3 Oxidation and Membrane Separation Units for Treatment of Industrial Laundry Wastewater